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Back to the foundry
Posted: Sat Nov 12, 2022 4:59 pm
by Rasper

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After several years of making sculpture in welded wire, I am returning to my foundry.
The clay model has been ready for four years, so my first step is to make a rubber mold of the clay model.
I shall use shims cut from cut up coffee cans. After cutting the cans into strips, I need to make keys in the strips for alignment purposes. (Rather than go to length to explain in words what I mean, for those of you who are sand casters, I shall let the series of photographs that will follow over the next few days do the explaining.)

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- IMG_0624.JPG (79.19 KiB) Viewed 10483 times
I have been away from the foundry for too long.
Richard
Re: Back to the foundry
Posted: Sat Nov 12, 2022 8:10 pm
by cae2100
Looks good richard, it looks like quite a large model. Will you just be casting it in pieces and welding it together or just casting it all as one piece?
Re: Back to the foundry
Posted: Sun Nov 13, 2022 8:41 am
by Jammer
Very nice, I really like the sax too. How tall is she?
Re: Back to the foundry
Posted: Sun Nov 13, 2022 4:37 pm
by Rasper
The sax is six feet tall. The girl is not large. She is about 16 inches tall. I'm too old to be casting large pieces now. A #30 crucible full of molten bronze has to be given some respect .
Richard
Re: Back to the foundry
Posted: Sun Nov 13, 2022 7:02 pm
by Jammer
30 pounds would be a huge pour for me.
Re: Back to the foundry
Posted: Sun Nov 13, 2022 7:28 pm
by Harry
Nice Richard, will be looking forward to following the progress on this.
Re: Back to the foundry
Posted: Tue Nov 15, 2022 6:35 am
by Rasper
A #30 crucible is close to 90 pounds of bronze,
R
Re: Back to the foundry
Posted: Tue Nov 15, 2022 10:13 am
by Jammer
Oh, I use the ones from Legend Mining supplies. Their number corresponds to Kilos of copper. I have a couple #20 that is supposed to be 20 Kilos (44 pounds) of copper. I don't know why different companies have different scales. A lot use pounds of pounds of Aluminum. Which is about a third of copper.
Re: Back to the foundry
Posted: Tue Nov 15, 2022 12:04 pm
by cae2100
I think the crucible richard has is an A30, not a #30, which would result in 90lbs of bronze. salamander super crucibles usually are the ones that go by A prefix because the size is denoted by the amount of aluminum in lbs where as import or cheaper crucibles usually go by # prefix and is based off of weight in brass. I have an A10 crucible and it gives around 30lbs of cast iron, so I think the A30 is what he's talking about, not the #30. I think that's where everyone is mixed up at.
Re: Back to the foundry
Posted: Sat Jan 07, 2023 6:25 pm
by Rasper
I have spent the past three days in getting my foundry back into condition. Cleaning out the accumulated leaves and dirt, Replacing fuel hoses and the rope that hoists the oil tank to gravity feed level. Buying a fresh bag of plaster for the investment. (I always use fresh plaster.) Making the sheet-metal flask for investing the wax. (Shown below.) And ten or twenty other things.
We have a big art exhibition here on February 10 and 11, and it is staring me in the face.
I plan to make the polyurethane rubber mold of the clay figure tomorrow, make the plaster mother mold on Monday, make the wax on Monday or Tuesday, invest it on Wednesday, burn the investment out for five days in the kiln at between 900 and 1000 F, and then pour it.
The flask is sitting on the kiln base with the kiln body over it suspended from the gantry crane.
Richard